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Background: The characteristics of boron (B) isotopes in different organ samples of Brassica napus L. provide powerful insights for better understanding the nutrient effect and acquisition mechanism of B in plants. Method: Hydroponic experiments with B sources and constant pH controlled in the nutrient solution were carried out to explore the B isotopic signals in different plant organs during the growth of B. napus. Results: The B contents and δ11B values showed an increasing trend from roots to leaves and a decreasing trend from leaves to flowers. B absorption at the interface of plant-nutrient solution system is controlled by equilibrium process in a closed system with light isotopes preferentially absorbed into roots in B-sufficient and B-deficient media. A Rayleigh fractionation model was used to fit the fractionation of B isotopes with the accumulated distribution fraction during plant growth. The kinetic fractionation process of absorption causes the increased fractionation of B isotopes from the lower to upper compartment in different diffusion manners of B(OH)3. The light isotope preferentially bonds with pectin by chelate crosslinking group to form the cell wall with more 11B left in the sap. Conclusions: The results also suggest that the B isotope tool has the potential to enable identification of the B nutrient effect and the physiochemical mechanism in plants. [ABSTRACT FROM AUTHOR]

This paper discusses the way that energy and entropy can be regarded as storage functions with respect to supply rates corresponding to the power and thermal ports of the thermodynamic system. Then, this research demonstrates how the factorization of the irreversible entropy production leads to quasi-Hamiltonian formulations, and how this can be used for stability analysis. The Liouville geometry approach to contact geometry is summarized, and how this leads to the definition of port-thermodynamic systems is discussed. This notion is utilized for control by interconnection of thermodynamic systems. [ABSTRACT FROM AUTHOR]

Institutions are often regarded either as rules or as equilibria sustained by self-interested agents. I ask how these two theories can be combined. According to Philip Pettit's Virtual Control Theory, they explain different things: rules explain why regularities persist; self-interest why they are resilient. Thus, his theory reconciles the two theories by adjusting their domains of application. However, the available evidence suggests that rules and self-interest often combine as sources of motivation. Because of this, it is better to integrate the theories rather than to reconcile them. Inspired by Cristina Bicchieri's theory of social norms, I incorporate the notion of rule-following into a game-theoretic account of institutions. According to the resulting Rules-and-Equilibrium Theory, institutions are rule- or norm-governed social practices. The theory does not only explain their persistence and resilience, but also their fragility, which provides another reason for preferring the proposed integration to Pettit's reconciliation. [ABSTRACT FROM AUTHOR]

The development of mild methods to depolymerize polymers has become increasingly important in our current Age of Plastics, and ball‐mill grinding (BMG) is emerging as a promising candidate. In this report, we demonstrate that subjecting poly(α‐methyl styrene) (PMS) to BMG leads to high extents of depolymerization (up to 64 mol% of α‐methyl styrene was produced) with minimal side products after only minutes of grinding. Constrained geometries simulate external force (CoGEF) simulations and radical trapping experiments supported that the depolymerization was initiated by mechanochemical chain scission. Depolymerization proceeded despite bulk temperatures remaining far below that of the ceiling temperature of PMS. Control experiments suggested that the extent of depolymerization was equilibrium controlled. Polystyrene and poly(methyl methacrylate) also underwent depolymerization, although to a much lesser degree (up to 4% monomer produced), presumably due to their much higher ceiling temperatures. This work provides an entry point for further development of BMG as a tool for the depolymerization of vinyl polymers under mild conditions. [ABSTRACT FROM AUTHOR]

The isomerization of iridium(III) complexes with metalated N-heterocyclic carbene (NHC) ligands was studied. The fac isomers of complexes with 1-phenyl-3-methylbenzimidazolin-2-ylidene or 1-phenyl-3-benzylbenzimidazolin-2-ylidene ligands are transformed cleanly into the mer isomers when solutions of the complexes are treated with first HNTf2 and then NEt3. The transformation can be accomplished within a few minutes and the side product (NEt3H)(NTf2) is easy to separate. Spectroscopic and structural analyses indicate that the isomerization proceeds by protonation of the carbene ligand at the metalated phenyl group, accompanied by a fac → mer rearrangement of the carbene donors. An iridium complex with a 1-phenyl-1,2,4-triazolo[4,3-f]phenanthridine-based carbene ligand could not be isomerized under similar conditions, most likely because of its reduced conformational flexibility. [ABSTRACT FROM AUTHOR]

This paper investigates the time-consistent mean-variance reinsurance-investment (RI) problem faced by life insurers. Inspired by recent findings that mortality rates exhibit long-range dependence (LRD), we examine the effect of LRD on RI strategies. We adopt the Volterra mortality model proposed in Wang et al. [(2021). Volterra mortality model: actuarial valuation and risk management with long-range dependence. Insurance: Mathematics and Economics96, 1–14] to incorporate LRD into the mortality rate process and describe insurance claims using a compound Poisson process with intensity represented by the stochastic mortality rate. Under the open-loop equilibrium mean-variance criterion, we derive explicit equilibrium RI controls and study the uniqueness of these controls in cases of constant and state-dependent risk aversion. We simultaneously resolve difficulties arising from unbounded non-Markovian parameters and sudden increases in the insurer's wealth process. While the exiting literature suggests that LRD has a significant effect on longevity hedging, we find that reinsurance is a risk management strategy that is robust to LRD. [ABSTRACT FROM AUTHOR]

This paper studies open-loop equilibriums for a general class of time-inconsistent stochastic control problems under jump-diffusion SDEs with deterministic coefficients. Inspired by the idea of Four-Step-Scheme for forward-backward stochastic differential equations with jumps (FBSDEJs, for short), we derive two systems of integro-partial differential equations (IPDEs, for short). Then, we rigorously prove a verification theorem which provides a sufficient condition for open-loop equilibrium strategies. As special cases, a mean-variance portfolio selection problem and a time-inconsistent problem under non-exponential discounting are discussed. [ABSTRACT FROM AUTHOR]

In tidal environments, channel networks act as essential drainage pathways. Although the complex interactions between environmental factors have been studied extensively, the effects of the initial bathymetry on tidal network ontogeny are poorly understood. In this contribution, we used a numerical model to mimic a schematic tidal basin subjected to tidal forcing. The effects of the initial bathymetry and vegetation growth are analyzed by changing the features of randomly generated bed perturbation and the intertidal platform slope. Different perturbation densities mildly affect the growth of tidal networks, which, at equilibrium, share similar values in terms of channel length, tidal prism, and cross‐sectional area. The complexity and structure of channel networks are more sensitive to variations in the perturbation distribution. Increasing the initial bathymetry slope can shorten channels and reduce the tidal prism and drainage efficiency. Vegetation growth is found to invariably promote channel lengthening and narrowing, increasing the complexity and drainage efficiency of the system. An asymmetrical tidal forcing generally leads to longer channels and smaller unchanneled lengths. Under ebb‐dominant conditions, channels get deeper, and the increased channel length ensures a higher drainage efficiency. The insights of our study provide a deeper understanding of the environmental factors controlling the equilibrium morphology of tidal channel systems and their overall resilience. Further implications concern the restoration and management of coastal areas through the informed use of topographic changes and planting arrangements. Finally, accounting for the uncertainties associated with initial conditions is relevant when modeling other earth systems and comparing them with real systems. Plain Language Summary: Tidal channels form networks connecting the sea to the inner land and act as essential pathways in coastal landscapes to exchange water, sediments, and nutrients. The channel network morphology and its efficiency in draining the basin exhibit different sensitivities to environmental factors. In this study, the evolution of a tidal network is simulated using a modeling framework to analyze the effects of small topographic features, vegetation, and tidal conditions on tidal channel characteristics. Small topographic features can significantly enhance the complexity of the channel network and increase the number of branches. The presence of vegetation generally promotes channel expansion and improves the drainage efficiency. However, the effect of vegetation on channel drainage efficiency may become weaker when the basin is sloping to the sea. The drainage efficiency can be further enhanced under flood‐ or ebb‐dominant conditions. Furthermore, under ebb‐dominant conditions, the tidal channel system will dissect the tidal basin more efficiently, resulting in a higher drainage efficiency than in flood‐dominant conditions. These findings are relevant for assessing the resilience of tidal channel systems and could be useful for the design of restoration projects and the management of coastal areas. Key Points: Randomly distributed bed perturbations may increase channel drainage efficiency by changing the channel network structureVegetation promotes channel elongation and drainage efficiency, while a sloping basin has opposite effects due to reduced tidal prismEbb‐dominant conditions produce a rearrangement of total channel length and mean unchanneled length, ensuring a higher drainage efficiency [ABSTRACT FROM AUTHOR]

The coexistence of chloritoid and biotite in medium-pressure Barrovian terranes is quite uncommon, and the parameters controlling their equilibrium relations are still controversial. Various studies have already investigated the influence of pressure (P), temperature (T), bulk rock (X bulk) and fluid (X fluid) compositions on the stability of this assemblage. Here we apply forward thermodynamic modelling on amphibolite-facies metapelites from the upper portion of the Lesser Himalayan Sequence (eastern Nepal Himalaya) to test which parameters mostly influence the stability of the chloritoid + biotite assemblage. P – T isochemical phase diagrams calculated in the MnNKCFMASHTO system fail in reproducing the coexistence of chloritoid and biotite, predicting biotite appearance at higher temperatures than chloritoid breakdown. Neither the fluid composition (i.e. reduced H 2 O activity due to the presence of CO 2) nor a more oxidated state of the system favours their coexistence, while slightly H 2 O-undersaturated conditions expand the biotite stability field toward lower temperatures, allowing the development of the chloritoid + biotite assemblage. Kinetic factors could have further contributed to the stability of this assemblage: thermal overstepping of the chloritoid-consuming and staurolite-producing reaction, induced by the difficulty in the staurolite nucleation and/or by the sluggishness of chloritoid dissolution, could have enhanced the metastable persistence of chloritoid at temperatures compatible with the presence of biotite. Being the kinetics efficiency intrinsically linked to the degree of fluid availability, the two factors (i.e. H 2 O-undersaturated conditions and kinetics of the chloritoid-consuming reaction) were likely complementary rather than mutually exclusive. [ABSTRACT FROM AUTHOR]

Normal sperm flagellar shape and movement are essential for fertilization. The integral protein outer dense fiber 4 (ODF4) localizes to ODFs, but its function remains unclear. Adenylate kinase (AK) is a phosphotransferase that catalyzes the interconversion and controls the concentration equilibrium of adenine nucleotides. AK shuttles ATP to energy-consuming sites. Here, we report on the relationship of flagellar shape and movement with ODF4, AK1 and AK2 by using Odf4-deletion (Odf4−/−) mice. Soluble ODF4 is coimmunoprecipitated with AK1 and AK2 in Odf4+/+ spermatozoa. ODF4, AK1 and AK2 localize to whole flagella (plasmalemma, mitochondria, ODFs, and residual cytoplasmic droplets (CDs)), principal pieces, and midpieces, respectively. Odf4−/− sperm flagella lose ODF4 and reduce AK1 and AK2 but produce ATP. The flagellum is bent (hairpin flagellum) with a large CD in the midpiece. There is no motility in the midpiece, but the principal piece is motile. Odf4−/− spermatozoa progress backward and fail to ascend in the uterus. Thus, Odf4−/− males are infertile owing to abnormal flagellar shape and movement caused mainly by the loss of ODF4 with AK1 and AK2. This study is supported by the rescue experiment; the abnormalities and male infertility caused by Odf4 deletion were reversed by Odf4 restoration. [ABSTRACT FROM AUTHOR]

This paper thoroughly explores the formation of Schiff bases derived from salicylaldehydes and a conformationally restricted amino alcohol (1-amino-2-indanol), as well as the generation of 1,3-oxazolidines, a key heterocyclic core present in numerous bioactive compounds. We provide enough evidences, both experimental-including crystallographic analyses and DFT-based calculations on imine/enamine tautomerism in the solid state and solution. In the course of imine formation, a pentacyclic oxazolidine–oxazine structure could be isolated with complete stereocontrol, whose configuration has been determined by merging theory and experiment. Mechanistic studies reveal that, although oxazolidines can be obtained under kinetic conditions, the prevalence of imines obeys to thermodynamic control as they are the most stable structures. The stereochemical outcome of imine cyclization under acylating conditions leads to formation of 2,4-trans-oxazolidines. [ABSTRACT FROM AUTHOR]

During development, cortical neurons are produced in a temporally regulated sequence from apical progenitors, directly or indirectly, through the production of intermediate basal progenitors. The balance between these major progenitor types is critical for the production of the proper number and types of neurons, and it is thus important to decipher the cellular and molecular cues controlling this equilibrium. Here we address the role of a cell cycle regulator, the CDC25B phosphatase, in this process. We show that, in the developing mouse neocortex of both sex, deleting CDC25B in apical progenitors leads to a transient increase in the production of TBR11 neurons at the expense of TBR2+ basal progenitors. This phenotype is associated with lengthening of the G2 phase of the cell cycle, the total cell cycle length being unaffected. Using in utero electroporation and cortical slice cultures, we demonstrate that the defect in TBR2+ basal progenitor production requires interaction with CDK1 and is because of the G2 phase lengthening in CDC25B mutants. Together, this study identifies a new role for CDC25B and G2 phase length in direct versus indirect neurogenesis at early stages of cortical development. [ABSTRACT FROM AUTHOR]

We newly synthesized a series of homo‐ and hetero‐tetracene (Tc) oligomers to propose a molecular design strategy for the efficient exciton transport in linear oligomers by promoting correlated triplet pair (TT) dissociation and controlling sequential exciton trapping process of individual doubled triplet excitons (T+T) by intramolecular singlet fission. First, entropic gain effects on the number of Tc units are examined by comparing Tc‐homo‐oligomers [(Tc)n: n=2, 4, 6]. Then, a comparison of (Tc)n and Tc‐hetero‐oligomer [TcF3‐(Tc)4‐TcF3] reveals the vibronic coupling effect for entropic gain. Observed entropic effects on the T+T formation indicated that the exciton migration is rationalized by number of possible TT states increased both by increasing the number of Tc units and by the vibronic levels at the terminal TcF3 units. Finally, we successfully observed high‐yield exciton trapping process (trapped triplet yield: ΦTrT=176 %). [ABSTRACT FROM AUTHOR]

For the first time, the transformation of biobased 5-HMF derivatives succeeded in a 2 × [4 + 2] cascade cycloaddition reaction, leading to a drastic (3–5-fold) increase in molecular complexity as a result of one synthetic step. A new approach to the use of plant biomass in organic synthesis using a cascade Diels–Alder reaction of 5-HMF dimer derivatives with alkynes has been developed. This reaction proceeds under thermodynamic control, diastereoselectively and regioselectively, providing rapid access to compounds of high molecular complexity with the same synthetic availability as previously obtained regular cycloadducts. As a concept illustration, under conditions of kinetic control, cycloadditions of two molecules of dienophiles are realized, and the resulting products, when heated, rearrange into thermodynamically more favorable cascade products. Reaction pathways were studied in detail using quantum chemical calculations to reveal major factors influencing the selectivity of the process. Discovery of a new sustainability pathway should be noted – to date, oligomeric derivatives are considered a waste of 5-HMF degradation, while the present study highlights them as a valuable material for the synthesis of nonplanar scaffolds. [ABSTRACT FROM AUTHOR]

The paper aims to introduce inverse tensor variational inequalities and analyze their application to an economic control equilibrium model. More precisely, some existence and uniqueness results are established and the well-posedness analysis is investigated. Moreover, the Tikhonov regularization method is extended to tensor inverse problems to study them when they are ill-posed. Lastly, the policymaker's point of view for the oligopolistic market equilibrium problem is introduced. The equivalence between the equilibrium conditions and a suitable inverse tensor variational inequality is established. [ABSTRACT FROM AUTHOR]

Cobalt ferrites exhibit widely varied magnetic behaviour due to the presence of a miscibility gap leading to the formation of periodic self-assembled nanostructures via spinodal decomposition. Periodicity and amplitude of the compositional fluctuations can be controlled by thermodynamic and kinetic processing parameters which allows for careful tuning of the magnetic properties. Although reports have shown evidence of spinodal decomposition, there is a lack of detailed characterization of the magnetic interactions and reversal mechanisms in these materials. In this work we use high-resolution first order reversal curves (FORC) measurements to understand the underlying magnetic processes occurring in a cobalt ferrite with a nominal composition of Co1.8Fe1.2O4 before (calcined) and after spinodal decomposition (annealed). Additionally, FORC measurements with preconditioning fields were conducted to separate the interaction signatures at low coercive fields by biasing the sample in positive and negative mean fields. Microstructural characterization using TEM combined with EDS showed uniform chemistry in the calcined sample and the presence of Fe rich and Co rich regions in the annealed sample, due to spinodal decomposition. Signs of positive exchange interactions were observed in both calcined and annealed samples. This work presents the first detailed magnetic characterization of magnetic interactions in a nanostructured cobalt ferrite, and provides an example of magnetic characterization of nanostructured ferrites using FORC. [ABSTRACT FROM AUTHOR]

In permafrost regions with warm frozen soil, subgrade thaw-collapse phenomenon commonly occurs, facing thaw collapse problems of the existed frozen soil subgrade, thus it is difficult to use traditional methods such as active cooling and passive protection technology to stabilize the existed warm frozen soil subgrade. This study derives a novel stabilizer method, a long-short (L-S) cement-mixed batter pile composite foundation to stabilize the existed warm frozen soil subgrade. To solve the thaw-collapse problems in warm frozen soil subgrade, high water content and large compressibility characteristics were compared between soft soil and warm frozen soils. Theoretical analysis of heat conduction and numerical simulation of finite element model were used to study the freeze-thaw process and evaluate the stabilized effects of the L-S cement-mixed batter piles on the warm frozen soil foundation of the Qinghai-Tibet Highway. Furthermore, the thaw process and mechanical properties of foundation and piles were analyzed by introducing the hydration heat factor in the thermodynamic control equation. The results indicate that the thawing displacement of the existed warm frozen soil subgrade was reduced owing to the "support" and "grasp" effects of the L-S cement-mixed batter piles on the surrounding soil. The composite ground formed by strengthening the warm frozen ground with batter piles could considerably improve the bearing capacity of the existed warm frozen ground, effectively restrain the deformation of the upper embankment, and improve the strength of the ground. The analysis can provide method for the construction design of cement mixing batter pile foundation in cold regions. [ABSTRACT FROM AUTHOR]

The intersection traffic signal control is an essential means of urban traffic. To solve the problem of urban congestion, it is necessary to consider the optimal signal control strategy for intersections. Using the store-and-forward method of traffic control modeling, the in-queue vehicle number of the key signal phase as the payoff index, this paper designs an optimal intersection signal-timing strategy based on the game theory method. In this strategy, each key phase is regarded as a game player, and each player competes for the release time to maximize their own payoff and minimize the queue. To optimize the intersection efficiency, a game strategy is designed to achieve the Nash equilibrium state, which is the queueing equilibrium of each key phase. Finally, by VISSIM simulation, the total number of stops can be decreased by 5% to 10% compared with the MA-DD-DACC method. [ABSTRACT FROM AUTHOR]

November 30,2022) In recent years, a significant amount of study has been conducted on how to control the equilibrium of an electrical motorbike robot (EMBot). This is essential because a stable EMBot must be controlled by a reliable system. In this study, we explored a number of approaches for stabilizing an EMBot by using a control moment gyroscope (CMG). The momentum from a flywheel's rotation at a set speed is employed to counteract gravity and keep the EMBot balanced. To measure the roll angle of the EMBot, an inertial sensor is used. From generalized coordinate systems, a nonlinear mathematical model of the EMBot is derived using Lagrange's equation. Pole placement (PP) and linear-quadratic regulator (LQR) controllers are utilized to test and observe the system's stability. By determining the appropriate locations of the closed- loop poles in the PP controller and finding the optimal A-matrix value by selecting closed-loop characteristics in the LQR method, the performance of the system in maintaining stability can be identified. [ABSTRACT FROM AUTHOR]

The development of Pd‐ and Ni‐catalyzed reactions for C−C bond formation is one of the primary driving forces in modern organic synthesis and the fine chemical industry. However, understanding the role of conformational mobility in reaction mechanisms is a long‐standing challenge. We highlight the effect of a multirotamer (multiconformer) system on the effective Gibbs free energy of activation in the key C−C coupling process and promote the use of a simplified version of multiconformer transition state theory that is straightforward to apply. Multivariate regression helped to quantitatively map the effect of coupled organic substituents (their structural and electronic parameters), as well as to determine the relative activity of metals. We provide computational evidence for solvent control of the equilibrium in RE/C−C‐bond activation for some model complexes. We also demonstrate that Ni complexes, being unique in the catalysis of sp3‐sp3 couplings, can be more challenging for machine learning and computational chemistry. The modeling was performed at an exceptionally high level, DLPNO‐CCSD(T)/CBS//RIJCOSX‐PBE0‐D4/def2‐TZVP. The Conclusions section contains an infographic summarizing the key findings related to the fields of cross‐coupling catalysis, machine learning in catalysis, and computational chemistry. [ABSTRACT FROM AUTHOR]

Epoxy (EP) was copolymerized with polyamic acid (PAA, precursor of polyimide (PI)) with termanil monomers of (1) 4,4′-Oxydianiline (ODA) and (2) pyromellitic dianhydride (PMDA) individually to form (PI-O-EP) and (PI-P-EP) copolymers. The FTIR spectrum of PI-O-EP copolymerization intermediates shows that some amide-EP linkages were formed at low temperature and were broken at higher temperature; in additoin, the released amide was available for subsequent imidization to form PI. The curing and imidization of the amide groups on PAA were determined by reaction temperature (kinetic vs. thermodynamic control). In PI-P-EP, the released amide group was very short-lived (fast imidization) and was not observed on FTIR spectra. Formation and breakage of the amide-EP linkages is the key step for EP homopolymerization and formation of the interpenetration network. PI contributed in improving thermal durability and mechanical strength without compromising EP's adhesion strength. Microphase separations were minimal at PI content less than 10 wt%. The copolymerization reaction in this study followed the "kinetic vs. thermodynamic control" principle. The copolymer has high potential for application in the field of higher-temperature anticorrosion. [ABSTRACT FROM AUTHOR]

In this review, we aim to present new concepts for the revisited separation of enantiomers from racemic compounds and a protocol worth to be followed in designing the preparation of pure enantiomers. We have taken into account not only the influence of the properties (eutectic composition) and characteristics of the reactants (racemic compound, resolving agent), but also the behavior of the resulting diastereomers and the different conditions (e.g., crystallization time, solvents used, solvate-forming compounds, achiral additives, etc.). The examples discussed are resolutions developed by our research team, through which we will try to illustrate the impact of all these considerations, presenting the methodological investigations interpreting recent discoveries and observations. Some special solid-state analytical and structural investigations assisting us in the elucidation and invention design of the resolution processes of some active pharmaceutical ingredients, such as Tetramisole, tofisopam, and Amlodipine, are also shown. [ABSTRACT FROM AUTHOR]

The ternary phase diagram based on cellulose (cellulose polymer/mixed solvents/Water (non-solvent)) system has been measured at 30 °C for two sources of cellulose. Cellulose synthesized from fibers of cotton and olive significantly influences the behavior of the crystallization index, which can cause changes during the film formation process. The differences can be explained by the presence of amorphous areas linked to a higher disorder, which is highlighted by the X-ray diffraction analysis XRD (crystallinity rate was 15.6% versus 47.4% for acetylated cellulose). The experimental analysis was carried out on the coexisting phases and the determination of binodal curve. The cellulose film was formed based on the equilibrium diagram to control the structure, which showed some dependence between the composition data and the binary interaction parameters in order to achieve liquid–liquid phase separation. This system required a large amount of water (15–90 wt.% water) to affect the porous and fibrous structure of the film. Olive cellulose films with lower crystallinity have smaller diameter (38 nm), they can swells faster and their solubility increases more, unlike acetate cellulose (56 nm). It can be said that the solvent diffusion is greater in the amorphous domains due to their higher disorder resulting in easy accessibility. [ABSTRACT FROM AUTHOR]

The paper deals with the random time-dependent oligopolistic market equilibrium problem. For such a problem the firms' point of view has been analyzed in Barbagallo and Guarino Lo Bianco (Optim. Lett. 14: 2479–2493, 2020) while here the policymaker's point of view is studied. The random dynamic optimal control equilibrium conditions are expressed by means of an inverse stochastic time-dependent variational inequality which is proved to be equivalent to a stochastic time-dependent variational inequality. Some existence and well-posedness results for optimal regulatory taxes are obtained. Moreover a numerical scheme to compute the solution to the stochastic time-dependent variational inequality is presented. Finally an example is discussed. [ABSTRACT FROM AUTHOR]

Wave-dominated sandy beaches are highly valued by societies and are amongst the world's most energetic and dynamic environments. On wave-dominated beaches with unlimited sand supply and limited influence of tide and geology, beach change has long been conceptualised in the morphodynamic framework of Wright and Short (1984). Such framework describes the occurrence of beach types based on wave conditions and sediment characteristics across the complete reflective-dissipative spectrum. Building on theoretical work, field/laboratory measurements and monitoring programmes, the physical mechanisms underpinning this morphodynamic framework have been progressively unravelled. Cross-shore morphological changes are primarily controlled by equilibrium and beach memory principles with below (above) average wave conditions driving down-state (up-state) transitions associated with onshore (offshore) sediment transport. Such cross-shore behaviour mostly reflects the imbalance between the onshoredirected sediment transport driven by wave nonlinearities and the offshore-directed sediment transport driven by the undertow. Self-organised morphological instabilities resulting from different positive feedback mechanisms are primarily responsible for alongshore morphological variability and the generation of rhythmic morphological features, such as crescentic bars, rip channels and beach cusps. Critically, wave climate and changes in wave regimes are key in driving the coupled cross-shore and longshore behaviour that ultimately explains modal beach state and frequency-response characteristics of beach morphological time series. [ABSTRACT FROM AUTHOR]

Isotropic pairwise interactions that promote the self-assembly of complex particle morphologies have been discovered by inverse design strategies derived from the molecular coarse-graining literature. While such approaches provide an avenue to reproduce structural correlations, thermodynamic quantities such as the pressure have typically not been considered in self-assembly applications. In this work, we demonstrate that relative entropy optimization can be used to discover potentials that self-assemble into targeted cluster morphologies with a prescribed pressure when the iterative simulations are performed in the isothermal-isobaric ensemble. The benefits of this approach are twofold. First, the structure and the thermodynamics associated with the optimized interaction can be controlled simultaneously. Second, by varying the pressure in the optimization, a family of interparticle potentials that all self-assemble the same structure can be systematically discovered, allowing for a deeper understanding of self-assembly of a given target structure and providing multiple assembly routes for its realization. Selecting an appropriate simulation ensemble to control the thermodynamic properties of interest is a general design strategy that could also be used to discover interaction potentials that self-assemble structures having, for example, a specified chemical potential. [ABSTRACT FROM AUTHOR]

Since ferroelectric HfxZr1−xO2 is different from other ferroelectric doped-HfO2 materials in terms of the dopant sensitivity of the formation of a ferroelectric phase, the mechanism of formation of a ferroelectric phase is investigated in comparison with that in ZrO2. It is found that ferroelectric HfxZr1−xO2 follows a unique phase-transition pathway from tetragonal to monoclinic phases similar to that in other doped HfO2 materials. The phase diagram of the HfO2–ZrO2 solid-solution system is reconsidered thermodynamically by taking into account the effects of both film thickness and nonequilibrium fabrication conditions on structural phase stability. The formation mechanism of a ferroelectric phase in the HfxZr1−xO2 system over a wide range of Hf/Zr concentration ratios is qualitatively (but clearly) understandable from these thermodynamic considerations. Finally, it is demonstrated that both ferroelectric and antiferroelectric ZrO2 films can be formed on the same substrate by controlling the nucleation of monoclinic and tetragonal phases, respectively. [ABSTRACT FROM AUTHOR]

Since ferroelectric HfxZr1−xO2 is different from other ferroelectric doped-HfO2 materials in terms of the dopant sensitivity of the formation of a ferroelectric phase, the mechanism of formation of a ferroelectric phase is investigated in comparison with that in ZrO2. It is found that ferroelectric HfxZr1−xO2 follows a unique phase-transition pathway from tetragonal to monoclinic phases similar to that in other doped HfO2 materials. The phase diagram of the HfO2–ZrO2 solid-solution system is reconsidered thermodynamically by taking into account the effects of both film thickness and nonequilibrium fabrication conditions on structural phase stability. The formation mechanism of a ferroelectric phase in the HfxZr1−xO2 system over a wide range of Hf/Zr concentration ratios is qualitatively (but clearly) understandable from these thermodynamic considerations. Finally, it is demonstrated that both ferroelectric and antiferroelectric ZrO2 films can be formed on the same substrate by controlling the nucleation of monoclinic and tetragonal phases, respectively. [ABSTRACT FROM AUTHOR]

Metal–organic cages (MOCs) have become an intensely studied class of abiotic host molecules. This is due to the ability to generate a myriad of polyhedral architectures from relatively simple, and minimal numbers of, components in high yield and under thermodynamic control. The encapsulation of molecular guests within the nanoscale, confined cavities of these cages frequently draws comparisons with enzymatic binding sites. In this regard, the ostensible ease with which chemical modifications can be made to these internal cavities adds to their attractiveness, as they can be readily tailored with a high degree of precision. In this Feature Article, the ways in which the cavities of MOCs can be engineered at the molecular level will be looked at. The discussion will be divided across three key parameters: size, shape and functionality. Most concepts will be exemplified with a focus on the Pd2L4 class of assemblies due to their relative structural simplicity and the wealth of studies reported in the literature. The core principles discussed will, however, be generalisable to other classes of MOCs, and abiotic host systems as a whole. Gaining increasing mastery over the fine tuning of MOC cavity properties, whilst retaining facile, high-fidelity self-assembly processes, will lead to ever more precise engineering of the cavities of artificial host systems with complex and highly specific functionality. [ABSTRACT FROM AUTHOR]

Despite the success of continuous glucose measuring systems operating through the skin for about 14 days, long‐term implantable biosensors are facing challenges caused by the foreign‐body reaction. We present a conceptually new strategy using catalytic enzyme‐based biosensors based on a measuring sequence leading to minimum disturbance of the substrate equilibrium concentration by controlling the sensor between "on" and "off" state combined with short potentiometric data acquisition. It is required that the enzyme activity can be completely switched off and no parasitic side reactions allow substrate turnover. This is achieved by using an O2‐independent FAD‐dependent glucose dehydrogenase embedded within a crosslinked redox polymer. A short measuring interval allows the glucose concentration equilibrium to be restored quickly which enables the biosensor to operate under quasi‐equilibrium conditions. [ABSTRACT FROM AUTHOR]

The treatment of cis-[PtCl2(XylNC)2] with thiazol-2-amines in a 2:1 ratio leads to a regioisomeric mixture of two binuclear complexes. These regioisomers are products of kinetic and thermodynamic control capable of regioisomerization. When the same reaction is carried out with a 5-fold excess of thiazol-2-amine, the nucleophile is able to react with the in situ-formed binuclear platinum(II) complexes, yielding a new type of bis-carbene platinum species. All new isolated compounds were characterized by 1H, 13C{1H}, and 195Pt{1H} NMR spectroscopy, high-resolution ESI-MS, and single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Background: Peripheral sensory and motor nerves are often affected in people with diabetes mellitus (DM), and balance problems are widespread. Diabetic peripheral neuropathy is common. This study investigated the impact of exercise treatment on balance parameters in diabetic peripheral neuropathy patients. Method: Electronic databases, such as PubMed, Web of Science, and Science Direct, were used to perform a search of accessible papers. The search strategy was (exercise therapy OR physical activity) AND (balance OR equilibrium OR postural control OR fall OR fall risk OR static balance OR dynamic balance OR functional balance) AND diabetic peripheral neuropathy. The Physiotherapy Evidence Database (PEDro) scale was used to rate the research in this review for its quality and reliability. Scores ranged from 5 to 9 on the PEDro scale. Result: According to databases, about 9,103 articles were found in August 2021 from March 1984 to February 2020. From 9103 articles, 3872 were deleted for different reasons, including duplicate, non-randomized controlled trial (RCT) articles and after reviewing the title and abstract. About 5,231 articles were found in free full text. In the end, 12 submissions were approved. These studies investigated the effects of exercise treatment on static, dynamic, and functional balance parameters in diabetic peripheral neuropathy patients. Conclusions: This study showed the positive effects of balance and strengthening exercise on static balance indices in patients with diabetic peripheral neuropathy. [ABSTRACT FROM AUTHOR]

In high production gas wells, premium connections are subject to alternating loads and vibration excitation due to the change of fluid pressure exerted on the tubing string. The energy dissipation on the sealing surface of premium connections affects the sealing performance of premium connections. The present study proposes a new energy dissipation analysis method for the sealing performance of premium connections using a microslip shear layer mode, a novel technique to overcome and improve the limitations of existing analysis method of premium connections. In this paper, based on a microslip shear layer model, a vibration equilibrium equation of premium connection was established with the constraints of the taper of the sealing surface, the thread, and the torque shoulder. Then, the control equilibrium equations of the stick and microslip were derived, and the critical microslip tangential force and force–displacement hysteresis curves under different interface parameters were obtained by solving the equilibrium equations. The influence of different interface parameters on the energy dissipation of premium connection was discussed by using a standardized regression coefficient method. It was found that the friction coefficient influenced both the minimum and maximum microslip tangential forces, while the shear layer stiffness influenced only the minimum microslip tangential force. The greater the stiffness of the shear layer, the smaller the minimum microslip tangential force and the relative displacement of the contact surface, which made it easier to generate energy dissipation. The influence of the friction coefficient on energy dissipation was much greater than the stiffness of the shear layer. There was positive correlation between the friction coefficient and energy dissipation. While, there was a negative correlation between the stiffness of shear layer and energy dissipation. The results can provide a theoretical guide for micro sealing failure mechanism of premium connections under dynamic loads and expand the analysis method of metal seals. [ABSTRACT FROM AUTHOR]

Glycolysis is an ancient, widespread, and highly conserved metabolic pathway that converts glucose into pyruvate. In the canonical pathway, the phosphofructokinase (PFK) reaction plays an important role in controlling flux through the pathway. Clostridium thermocellum has an atypical glycolysis and uses pyrophosphate (PPi ) instead of ATP as the phosphate donor for the PFK reaction. The reduced thermodynamic driving force of the PPi PFK reaction shifts the entire pathway closer to thermodynamic equilibrium, which has been predicted to limit product titers. Here, we replace the PPi PFK reaction with an ATP-PFK reaction. We demonstrate that the local changes are consistent with thermodynamic predictions: the ratio of fructose 1,6-bisphosphate to fructose-6-phosphate increases, and the reverse flux through the reaction (determined by 13C labeling) decreases. The final titer and distribution of fermentation products, however, do not change, demonstrating that the thermodynamic constraints of the PPi PFK reaction are not the sole factor limiting product titer. IMPORTANCE The ability to control the distribution of thermodynamic driving force throughout a metabolic pathway is likely to be an important tool for metabolic engineering. The phosphofructokinase reaction is a key enzyme in Embden-Mayerhof-Parnas glycolysis and therefore improving the thermodynamic driving force of this reaction in C. thermocellum is believed to enable higher product titers. Here, we demonstrate switching from pyrophosphate to ATP does in fact increases the thermodynamic driving force of the phosphofructokinase reaction in vivo. This study also identifies and overcomes a physiological hurdle toward expressing an ATP-dependent phosphofructokinase in an organism that utilizes an atypical glycolytic pathway. As such, the method described here to enable expression of ATP-dependent phosphofructokinase in an organism with an atypical glycolytic pathway will be informative toward engineering the glycolytic pathways of other industrial organism candidates with atypical glycolytic pathways. [ABSTRACT FROM AUTHOR]

Based on numerous imaging and electrophysiological studies, the presupplementary motor area (pre-SMA) and the rostral cingulate motor area are cortical regions considered to be essential to voluntary movement initiation and behavioral control. However, their respective roles and functional interactions remain a long-standing and still debated question. Here, we trained 2 rhesus monkeys (Macaca mulatta) in a complex cognitive task to compare the neuronal activity of these 2 regions on the medial wall during both perceptual and internally guided decisions. We confirmed the implication of both areas throughout the decision process. Critically, we demonstrate that instead of a stable invariant role, the pre-SMA and rostral cingulate motor area manifested a versatile hierarchical relationship depending on the mode of movement initiation. Whereas pre-SMA neurons were primarily engaged in decisions based on perceptual information, rostral cingulate motor area neurons preempted the decision process in case of an internally doubt-driven checking behavior, withholding pre-SMA recruitment during the time spent inhibiting the habitual action. We identified a versatile hierarchical organization of the mediofrontal area that may substantially affect normal and pathological decision processes because adaptive behaviors, such as doubt-checking and its compulsive counterpart, rely on this subtle equilibrium in controlling action initiation. [ABSTRACT FROM AUTHOR]

Advances in peptide and protein therapeutics increased the need for rapid and cost-effective polypeptide prototyping. While in vitro translation systems are well suited for fast and multiplexed polypeptide prototyping, they suffer from misfolding, aggregation and disulfide-bond scrambling of the translated products. Here we propose that efficient folding of in vitro produced disulfide-rich peptides and proteins can be achieved if performed in an aggregation-free and thermodynamically controlled folding environment. To this end, we modify an E. coli-based in vitro translation system to allow co-translational capture of translated products by affinity matrix. This process reduces protein aggregation and enables productive oxidative folding and recycling of misfolded states under thermodynamic control. In this study we show that the developed approach is likely to be generally applicable for prototyping of a wide variety of disulfide-constrained peptides, macrocyclic peptides with non-native bonds and antibody fragments in amounts sufficient for interaction analysis and biological activity assessment. Generic approach for rapid prototyping is essential for the progress of synthetic biology. Here the authors modify the cell-free translation system to control protein aggregation and folding and validate the approach by using single conditions for prototyping of various disulfide-constrained polypeptides. [ABSTRACT FROM AUTHOR]

Herein, we present the narcissistic self-sorted state from two kinds of structurally similar tritopic ligands with a cis-protected Pd(II) complex, which was generated by both the pathway-dependent process and the proper choice of the leaving ligand. This metastable state could not be attained by simple mixing of all components by heating under thermodynamic control. [ABSTRACT FROM AUTHOR]

In this study, whether raw shrimp shell (Shr-S), which is included in the waste material category, can be used to remove cobalt (Co2+), which is among the heavy metals with a high toxicological risk level, from aqueous environments and the effect of this material on the treatment process were examined. To be able to understand the effect of Shr-S use as an adsorbent on Co2+ adsorption, the effects of pH levels (2.0–7.0), Shr-S dose (0.5–5.0 g), and contact time (5–120 min) were examined throughout the adsorption. At optimum conditions for Shr-S (dose: 1 g/L, pH: 5.26, time: 10 min), the Co2+ removal efficiency was found to be about 75 %. The surface structure of Shr-S was revealed by FTIR and SEM-EDX analyses. Equilibrium and speed control were determined using four different isotherm and kinetic models. It was found to be more appropriate for the pseudo-second-order kinetic and Langmuir, whose correlation coefficients (R2) were 0.9966 and 0.9567, and the maximum capacity was calculated as 7.692 mg/g. Results of this study revealed that in terms of removal of Co2+ from aqueous environments, Shr-S can be used as an effective adsorbent and its adsorption capacity is comparable to other adsorbents studied in the literature. • To research the feasibility of using the Shr-S as a low-cost adsorbent for Co2+. • The use of Shr-S that are classified as garbage is an innovative approach. • We try to summarize the various operating conditions used for Co2+ yield on Shr-S. • Shr-S was used as a natural adsorbent due to its easily accessible, applicability. • The Shr-S was used without any chemical modification. [ABSTRACT FROM AUTHOR]

(1) Background: A mouth-free interface is required for functional electrical stimulation (FES) in people with spinal cord injuries. We developed a novel system for clenching the human metacarpophalangeal (MP) joint using an earphone-type ear canal movement sensor. Experiments to control joint angle and joint stiffness were performed using the developed system. (2) Methods: The proposed FES used an equilibrium point control signal and stiffness control signal: electrical agonist–antagonist ratio and electrical agonist–antagonist sum. An angle sensor was used to acquire the joint angle, and system identification was utilized to measure joint stiffness using the external force of a robot arm. Each experiment included six and five subjects, respectively. (3) Results: While the joint angle could be controlled well by clenching with some hysteresis and delay in three subjects, it could not be controlled relatively well after hyperextension in the other subjects, which revealed a calibration problem and a change in the characteristics of the human MP joint caused by hyperextension. The joint stiffness increased with the clenching amplitude in five subjects. In addition, the results indicated that viscosity can be controlled. (4) Conclusions: The developed system can control joint angle and stiffness. In future research, we will develop a method to show that this system can control the equilibrium point and stiffness simultaneously. [ABSTRACT FROM AUTHOR]

We consider a non-classical 2D mathematical equilibrium model describing a possible mechanical contact of a composite structure having a sharp-shaped edge. Nonlinearity of the model is caused by conditions of inequality type for a corresponding variational problem. The main feature of this basic model consists in its geometrical configuration, which determines non-convexity of the problem under consideration. Namely, the composite in its reference state touches a wedge-shaped rigid obstacle at a single contact point. On the basis of this model, we consider an induced family of problems depending on different functions of external loads. For a given set of functions, describing admissible external loads, we formulate an optimal control problem, where functions of external loads serve as a control. A cost functional is given with the help of an arbitrary weakly upper semicontinuous functional defined on the Sobolev space of feasible solutions. The solvability of the optimal control problem is proved. Furthermore, for a sequence of solutions corresponding to a maximizing sequence, a strong convergence in the corresponding Sobolev space is proven. [ABSTRACT FROM AUTHOR]

Several missions have reported complex alteration mineralogies on early Mars, which preserve environmental records of multiple water-rock-atmosphere interactions. The MSL and M2020 missions in Gale and Jezero have identified Fe and Mn-bearing secondary phases. These elements are used as tracers for the redox conditions on both Earth and Mars. However, to fully understand the short-lived and local-scale processes observed on Mars, it is necessary to go beyond thermodynamic models and experiments. Enhancing our ability to interpret the redox and hydrological conditions from the observed phase assemblage requires understanding the evolution of Fe and Mn during weathering. This study reports the results of kinetic alteration experiments and geochemical models conducted under Mars-like conditions. We tested variable pO 2 , pCO 2 , temperatures, and starting solutions. The results suggest that Fe is more mobile on Mars than on Earth, with a pseudo-equilibrium concentration that is kinetically controlled by dissolution and oxidation rates. Despite some initially modeled siderite precipitation, no siderite precipitation was observed in the altered powder. Solutions with higher acid concentrations were primarily controlled by dissolution kinetics, with both Fe and Mn being mobile, even when a minor amount of P, Fe, and S bearing secondary phases are formed. Based on our experimental results, we updated the model and conducted two large-scale sensitivity tests on our kinetic simulation. We confirmed that our experiments were too high in pO 2 for siderite to form; however, we found that over a range of clearly oxidizing conditions from an equilibrium standpoint, Fe and Mn are mostly mobile, and siderite precipitation can occur. We were able to determine the pO 2 , pCO 2 and the temporal space where Fe-oxide or siderite predominate or coexist, constraining the meaning of reducing or oxidizing conditions. Moreover, we also observed that siderite formation would require a much longer water residence time than Fe-oxide to precipitate, interpreted as higher weathering rates, or later evaporation required to effectively precipitate under any conditions. On ancient Mars, both Fe and Mn would be relatively mobile and prone to be leached from their host rock. Observing siderite or oxide would not primarily be a redox marker but would be a clue to a different hydrological regime. At the planetary scale, it would be challenging to form authigenic siderite during alteration. Although siderite would not indicate the presence of a particularly reducing atmosphere and that Mn-oxides are mainly pH controlled and do not require terrestrial-level amounts of oxygen, a collocated precipitation of siderite and Mn-oxides could also provide valuable information to constrain the redox environment of the ancient Mars. • Iron and Manganese are much more mobile on Mars than on Earth. • Concentrations are controlled by steady-state equilibrium between kinetic rates. • Siderite can form in oxidizing conditions compared to previous equilibrium models. • The pO2 and pCO2 window for the formation of siderite or Fe-oxide was determined. • Siderite precipitation is more of a clue of a change in hydrology than in redox. [ABSTRACT FROM AUTHOR]

• Two approaches for modeling heat pumps at full- and part-load operation are compared. • The sensitivity of energy results with the modeling used in a demand response event is investigated. • The approach based on correcting factors of rating data underestimates seasonal energy performance. • Lowering the temperature setpoint may result in an increased number of compressors cycling. • Integrated modeling enables the adjustment of controller parameters to safely operate heat pumps. Reversible heat pumps are key technologies for the decarbonization of space heating and cooling in buildings. Considering the ongoing research on these technologies, it is important to build models that better describe heat pump operation when installed in the field, allowing for a more precise estimation of energy savings. Most studies are usually based on models that reproduce heat pump operation at part load by correcting factors taken from Standards or catalogs. The risk of incorrectly estimating the achievable energy savings is therefore real, as is the adoption of physically unfeasible operating strategies. The present study compares an approach based on correcting factors, with a more complete one in which both the thermodynamic model and control are considered. For an office building in the Mediterranean region, the performance of an air-to-water heat pump is evaluated using both approaches during the entire heating and cooling seasons and in the case of a demand response event. The results show that the typical approach leads to a large variation in estimated performance in the case of low demand with a percentage variation of more than 50%. In addition, about 15.3% overestimation in carbon dioxide emissions is found. In the case of a demand response event that involves reducing the temperature setpoint of the heat pump, disregarding the controller's action could lead to a significant underestimation (from 65% up to 118%) of the achievable energy savings. Additionally, the integrated approach revealed a compressor overcycling in the case of controller dead-band variation (more than 12 compressor cyclings in one hour), which could not be detected by a simplified approach. This study confirms the importance of including a more comprehensive modeling of heat pumps in energy flexibility studies to obtain more accurate estimate of the achievable energy and environmental impacts. [ABSTRACT FROM AUTHOR]

We provide a new generalized framework accounting for the effects of water and nutrient uptake by roots in the weathering zone on broad patterns of solute concentration - discharge relationships in rivers. As plants withdraw water from the subsurface, they decrease the area-normalized fluid drainage rate. This results in a discharge flux to springs and streams which is a function of water use by plants, leading to ecosystem regulation of the characteristic timescales of chemical weathering reactions and fluid flow rate. Our predictive framework quantifies the pore water and river solute chemistry generated from water-rock interactions, regulated by the effects of vegetation on water flow rates. To this we add the capacity for vegetation to enrich, passively admit, or discriminate against a given dissolved solute based on ecophysiological needs, thus further modifying the local concentration of a given chemical species in solution across a weathering profile. This uptake flux is not lost to the atmosphere in the same manner as water is removed from the subsurface via evapotranspiration. Rather, these extracted chemical species become incorporated into the topsoil as litter which may be partially or fully resolubilized, creating an upper boundary condition which depends on the uptake and recycling characteristics of the ecosystem. These processes are united through a new solution to the advection-reaction equation which allows vegetation to regulate broad patterns of stream concentration - discharge relationships. We show that ecosystems are capable of both accelerating and impeding water-rock reaction rates across the weathering profile, ultimately leading to both thermodynamic and ecological controls on the baseflow concentration of rock-derived solutes in rivers. • We offer a new predictive model for the water and nutrient demands of ecosystems. • Plants to both enhance and impede mineral weathering reactions. • Plants modulate the relationship between river chemistry and flow rate. • River chemistry reflects both thermodynamic and ecological controls. [ABSTRACT FROM AUTHOR]

• Stabilities of cholestane isomers are studied with the density functional theory. • The isomeric ratios of cholestane are found to be governed thermodynamically. • The length of the side chain has little effect on the isomeric ratios. • The energy difference between isomers stems from 1,3-diaxial interactions. Cholestane is produced by diagenesis of cholesterol in the geosphere being known to have four main stereoisomers. The abundance ratios of these stereoisomers are important indicators of the geospheric thermal history. However, it has been unclear whether the isomeric ratios are caused by kinetic or thermodynamic dominance. In this study, we analyzed the isomeric ratios of cholestane under thermodynamic dominance using the density functional theory. The calculated isomeric ratios are in good agreement with the limit values in the geosphere, indicating that the isomeric ratios in the geosphere can be obtained under thermodynamic control. We also discussed the factors contributing to their stabilities. [ABSTRACT FROM AUTHOR]

The article titled "Cover Feature: Self-Assembled Bis-Acridinium Tweezer Equilibria Controlled by Multi-Responsive Properties" discusses the control of equilibria in supramolecular systems. The conditions that affect these equilibria include the interaction between molecules and the solvent, as well as external stimuli such as temperature, electrons, and protons. The article provides more information on this topic and is authored by V. Heitz, H.-P. Jacquot de Rouville, and their colleagues. [Extracted from the article]

[Display omitted] • The Δ G ≠×Δ G (R → P) indicator was proposed to explain the difference in the scavenging performance of various anti-agers. • The strong positive correlation between experimental residues and Δ G ≠×Δ G (R → P) values (R2 = 0.806) was disclosed. In this article, the radical scavenging performance of eight anti-agers (TMQ , ETMQ , DCD , o-MBp24 , o-MBp14 , p-BBp14 , DNPD , and 6PPD) was benchmarked by the experimental residue rates of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, followed by the theoretical investigation from the perspective of both kinetic and thermodynamic factors. Kinetically, anti-agers with lower Gibbs free energy barriers (Δ G ≠) presumably exhibit higher scavenging performance. Moreover, the scavenging performance is also controlled by the thermodynamic feature, that is, the small difference in Gibbs free energy between products and reactants (Δ G (R → P)) promotes the scavenging performance. Therefore, the Δ G ≠×Δ G (R → P) indicator considering both kinetic and thermodynamic contributions was proposed here to comprehensively explain the difference in the scavenging performance of anti-agers. The strong positive correlation between experimental residues and Δ G ≠×Δ G (R → P) values (R2 = 0.806) revealed that the Δ G ≠×Δ G (R → P) indicator promises to be a reliable metric to theoretically assess the scavenging performance of anti-agers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Models consider groundwater (GW) inflow, conduction, shading, and other heat fluxes. • Equilibrium temperature deficit concept is used as scenario comparative benchmark. • GW inflow and riparian shading most strongly drive changes in temperature signals. • These scenarios support process-based interpretation of paired air–water metrics. • GW source depth and inflow magnitude affect climate change thermal resilience. Headwater stream temperature often exhibits spatial variation at the kilometer-scale, but the relative importance of the underlying hydrogeological processes and riverine perturbations remains poorly understood. In this study, we investigated the relative importance of groundwater (GW) and other processes on downstream annual stream temperature signal characteristics using deterministic heat budget model (HFLUX) scenarios within an idealized stream reach representative of mountainous forested conditions. We summarized annual stream thermal regimes from the relationship of paired sinusoidal air and water temperature signals (amplitude ratio, phase lag, and mean ratio). Results showed that downstream changes in annual temperature depended on the thermal gradient between water and the hypothetical equilibrium temperature (where all heat fluxes sum to zero). GW inflow, riparian shading, and the boundary input signal were the most significant factors affecting downstream annual water temperature signals, while flow volume and channel dimensions impacted how quickly annual temperature signals changed. Effects of GW were dominated by advective rather than conductive heat exchange processes, but conduction played a larger role when GW input was more spatially diffuse. Our results indicated several mechanisms by which local processes may affect stream thermal resilience to disturbances and can help guide management of wildfire and climate change. [ABSTRACT FROM AUTHOR]

Equilibrium isotope fractionation factors are crucial to quantitatively interpreting Ca isotope data of natural samples. Recent studies have revealed significant equilibrium Ca isotope fractionation between minerals, but the controlling factors remain poorly understood. Using density functional theory, this study calculates the reduced partition function ratios (RPFRs) among amphiboles (richterite and tremolite), sorosilicates (akermanite and gehlenite), K-bearing carbonates (butschliite), Na-bearing diopside (jadeite), and other Ca-bearing minerals (fluorapatite, anhydrite, CaTiO 3 perovskite, and fluorite) at 0 GPa. The RPFRs of diopside and anorthite over a pressure range from 0 to 5 GPa are calculated to investigate the pressure effect. The effect of force constant, bond length, coordination number, anion type, solid solution composition, and pressure on RPFRs are discussed by compiling the literature data. The RPFRs show good correlations with the force constant and bond length but have no clear correlation with the coordination number. This suggests that the bond length is more reliable than the coordination number for roughly predicting the signs and magnitudes of inter-mineral isotope fractionation. Na-bearing clinopyroxene (e.g., jadeite) has similar RPFR with Na-free clinopyroxene, suggesting that the jadeite effect should be insignificant in natural samples. The RPFR of anorthite is lower than that of diopside at low pressure, and the two minerals both show a positive correlation between RPFR and pressure. Notably, the heavy Ca isotope enrichment between these two minerals can be reversed at high pressure (>3 GPa at 1000 K) because anorthite's RPFR changes more sharply with increasing pressure than that of diopside. However, such a reverse may not occur in Earth's modern crust due to the stability of anorthite at lower pressures. Combining the theoretical predictions of amphibole and plagioclase and natural sample observation on granitoids, we infer that the RPFR of granitic magma may be lower than that of basaltic magma. [ABSTRACT FROM AUTHOR]

Compared to pulse detonation engine and rotating detonation engine, oblique detonation engine has the advantage of higher flight Mach number. However, it is still challenging to achieve stabilized oblique detonation wave for a broad range of flight conditions. To control oblique detonation wave, this study focuses on the oblique detonation wave structure evolution induced by changing the wedge angle. Transient two-dimensional simulations are conducted for wedge-stabilized oblique detonation wave in a stoichiometric hydrogen/air mixture. The detailed chemistry of hydrogen combustion is considered, and the thermal states of the reactants are determined by the specified flight altitude and the Mach number. The angle change between inflow and wedge can be achieved in two ways: inflow-angle change with fixed wedge angle and wedge-angle change with fixed inflow direction. Results indicate that no new autoignition zone exists in the transient wave evolution caused by wedge-angle change, which is different from that of inflow-angle change observed in previous studies. For the wedge-angle change process, the effects of wedge-angle change rate on transient oblique detonation wave structure evolution are further assessed. It is found that the transient oblique detonation wave structure is more sensitive to the wedge-rotation angular velocity for increasing wedge angle (controlled by the thermodynamic properties of the mixture) than that for decreasing wedge angle (controlled by the shock wave dynamic). For the quasi-steady triple-wave structure during wedge-angle decreasing process, a normal detonation wave occurs and becomes dominant in the wave structure evolution, whose formation mechanism is analyzed by the polar curve theory. [ABSTRACT FROM AUTHOR]